What I'm looking for is an audio graphic equalizer that gives complete and independent control of both L and R channels in playback mode for whatever is coming out through the PC's speakers or headphones.
If I want to increase the volume of the audio at 4kHz, or any other value, in the L channel while decreasing its volume at that value in the R channel. I want to be able to.
The drivers and utilities for the MoBo's on board sound, and any other graphic equalizer with a media player, or any add-on graphic equalizer that I have been able to find so far only allows any changes to be made equally to both channels. What is done to one is done to the other. They cannot be independently controlled. What I want is complete and independent control of both audio channels. That should allow the PC's speakers and/or headphones to be tuned to the specific hearing capability of an individual listener.
As close as I can think of a way to accomplish this would be to split the L & R channels into independent mono channels, make the changes wanted to each separate channel, then recombining them back into stereo again. That would work for recording audio. But, I do not see that as working for playback. I'm beginning to think that that what I am looking for may only be found in high-end audio engineering software.